Introducing a simple database Database tutorial (3)
MySQL database
MySQL database is a C\S structured software, which is divided into: client and server.
If you want to access the server, you must go through the client; the server should be running all the time, and the client should be running when needed.
Interactive method
Client connection authentication, that is, connecting to the server, authenticating the identity mysql.exe -hPup
-h, host address, localhost for local, IP address for remote
-P, port number, used to find software
-u, username
-p, password
Send SQL command;
The server accepts SQL instructions, then processes the SQL instructions and returns the operation results;
The client accepts the results and displays the results;
Due to server concurrency limitations, the connection needs to be disconnected (three instructions , respectively: exit, quit and \q), release resources.
Server Object
Since there is no way to fully understand the internal structure of the server, we can only roughly analyze the internal structure of the database server.
Generally speaking, the internal objects of the MySQL database server are divided into four layers, namely: Data Management System (DBMS) –> Database (DB) –> Table (Table) –> Field ( Filed).
The above is the detailed content of Introducing a simple database Database tutorial (3). For more information, please follow other related articles on the PHP Chinese website!

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